1 Samuel 24:8-10

Then David went out of the cave and called out to Saul, “My lord the king!” When Saul looked behind him, David bowed down and prostrated himself with his face to the ground. He said to Saul, “Why do you listen when men say, ‘David is bent on harming you’? This day you have seen with your own eyes how the LORD delivered you into my hands in the cave. Some urged me to kill you, but I spared you; I said, ‘I will not lay my hand on my lord, because he is the LORD’s anointed.’